Temperature and time dependence of diffusion of PCL into PVC

Abstract

AbstractThe phenomenon of diffusion between two joined polymers [poly(vinyl chloride) and poly(ε‐caprolactone)] has been investigated by light microscopy and electron microscopy of thin sections taken perpendicular to the interface. It has been established that the diffusion is unidirectional, i.e., PCL into PVC, and that the solubility is limited and increases with temperature. Chlorine x‐ray analysis has shown that the concentration profile consists of a sharp change at the PCL boundary and a gradual change at the diffusion front. The diffusion region morphology has been found to be inhomogeneous and reveals density fluctuations within the PVC matrix. The diffusion behavior is therefore different from the classical Fickian diffusion previously noted and can be well described by a sorption mechanism.